local voucherId = ARGV[1]
local userId = ARGV[2]
local orderId = ARGV[3]

local stockKey = 'seckill:stock:'..voucherId
local orderKey = 'seckill:order:'..voucherId
if(tonumber(redis.call('get', stockKey))<=0) then
    return 1
end
if(redis.call('sismember',orderKey,userId)==1) then
    return 2
end
redis.call('incrby',stockKey,-1)
redis.call('sadd',orderKey,userId)
--发送消息
redis.call('xadd','stream.orders','*', 'userId', userId, 'voucherId', voucherId, 'id', orderId)
return 0